New Rechargeable Battery Uses Water 179
fergus07 writes "Scientists at Stanford have developed a battery that uses nanotechnology to create electricity from the difference in salt content between fresh water and sea water. The researchers hope to use the technology to create power plants where fresh-water rivers flow into the ocean. The new 'mixing entropy' battery alternately immerses its electrodes in river water and sea water to produce the electrical power."
yea (Score:2)
so does the one in my lawnmower, I thought lead acid batteries have been around a while, maybe I just live in the future
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But, but, this has the word "nano" in it! It has to be good!
http://www.google.com/trends?q=nano&ctab=0&geo=all&date=all&sort=0 [google.com]
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its rechargeable and uses water, the title of this article makes that sound like a break through innovation, the method described is, but the title is dumb
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it was in response to the dipshit title, not the article
or I meant woosh!
WARNING (Score:3)
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adblock and/or noscript for the win ;)
Think Smaller (Score:4, Funny)
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I have a flashlight with the dynamo that charges when you shake it. So I just charge it when I... well it's personal - but my light is always charged.
Re:Think Smaller (Score:4, Funny)
New lemon orchard used to power city.
Clever academics have found a way to harness the power of a standard lemon with an old copper penny and some scrap zinc. Could this scale?
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Just think of the possibilities! (Score:5, Interesting)
We could use the generated electricity to power desalinisation plants.
Re:Just think of the possibilities! (Score:5, Interesting)
We could use the generated electricity to power desalinisation plants.
I think you are trying to be funny, but this actually makes sense, and there are proposals to do exactly this. Here is how it works:
The reason this works is that you are effectively collecting the solar energy that shines on the evaporation ponds.
Re:Just think of the possibilities! (Score:4, Interesting)
Not that this would be ecologically feasible but what if you dug a tunnel from the pacific ocean to death valley (-300 feet). Then you could get some power out of the potential water drop. Then as the water floods the valley it's so hot it would evaporate and you could keep letting the water in. The evaporated water would rain on the next mountain down wind and create arable land.
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Probably be more feasible for Mediterranean -> Dead Sea, but then you'd have to tunnel through numerous archaeological sites to do it.
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Siphons have a maximum theoretical height limit relating to the minimum pressure inside at the peak. Simply put when the pressure gets low enough to boil water at ambient temperature then the siphon no longer works.
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San Andreas Fault thinks your tunneling is cute.
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Interesting, but what's the advantage of this over condensing the vapour from the pools directly?
It is orders of magnitude less expensive. If you want to condense the vapor, you first need to collect the vapor. Evaporation ponds typically cover thousands of hectares. Building an enclosure to collect the vapor over such an area would cost megabucks or even gigabucks. Once you collect the vapor you need to compress and cool it to turn it into liquid water. This is also very expensive.
If simply evaporating seawater was a cost effective way to produce fresh water, the world would have not water shorta
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Isn't Step 1 already splitting seawater into fresh water and brine?
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No it doesn't work. Well, it would work, but it'd be less effective
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I think its easier to have acres and acres of solar collectors than it is to build a structure over the top of that.
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I see what you did there...
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I see what you did there...
But apparently the moderators didn't...
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Perpetual motion FTW!
Life on Earth is only perpetual until you turn off the sun.
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Isn't this already in practice elsewhere??? (Score:5, Informative)
I know the plans to put one of these into service are almost finalized in The Netherlands, spanning the "afsluitdijk"
http://wikimobi.nl/wiki/index.php?title=Zoet/zout_watergrens [wikimobi.nl]
But i think the Norwegians beat us all to it:
http://www.statkraft.com/energy-sources/osmotic-power/ [statkraft.com]
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Depends on how wide your definition of "this" is. Let's quote TFA for convenience:
Making electricity from the difference in salinity (the amount of salt) in fresh water and sea water is not a new concept. We've previously covered salinity power technology [gizmag.com], and Norway's Statkraft [gizmag.com] has built a working prototype power plant. But the Stanford team, led by associate professor of materials science and engineering Yi Cui, believes their method is more efficient, and can be built more cheaply.
Re:Isn't this already in practice elsewhere??? (Score:5, Funny)
...spanning the "afsluitdijk".
Cat just jump on your keyboard?
Re:Isn't this already in practice elsewhere??? (Score:4, Funny)
...spanning the "afsluitdijk".
Cat just jump on your keyboard?
Appropriately enough, the language sounds like a cat expectorating a hairball.
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How did you just guess the password to my credit card accounts?
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TFA explicitly mentions the Statkraft project. However, there seems to be a significant difference between the two; where statkraft is using the salinity to create pressure and power a conventional turbine generator, this article is about creating current directly, which should theoretically improve efficency a lot.
According to TFA a, 50cubic meter/second flow of fresh water could yield up to 100MW.
Bass Akwards! (Score:4, Insightful)
After the battery is discharged, the salt water is drained and fresh water is added to begin the cycle again.
This is awesome, we can use up all our fresh water and would have an unlimited supply of salt water!
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Re:Bass Akwards! (Score:4, Insightful)
You do know that there is an amazingly simple way to separate the salt from the water, right? It is called evaporation.
The concepts of desalination are certainly quite simple, its the economics that are complicated.
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You do know that there is an amazingly simple way to separate the salt from the water, right? It is called evaporation.
The concepts of desalination are certainly quite simple, its the economics that are complicated.
He means natural evaporation. Oceans are under the Sun all the time. You can't "use up" fresh water by intercepting water that's about to fall on the ocean and making it into salt water. That is happening all the time anyway, those rivers are constantly dumping fresh water into the ocean. Luckily, water evaporates off the oceans and comes back down as fresh water as rain, filling up those rivers and continuing the cycle.
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This certainly wouldn't be appropriate everywhere. But, consider the Mississipi River Delta. It's dumping massive amounts of fresh water into salt water anyhow.
It hardly seems like diverting a small percentage of the fresh water being dumped into the ocean by nature, extracting power from it as it gets salty, then dumping the brackish water from the power plant into the ocean, in any reasonable way reduces the fresh water supply, does it?
Or, do you propose that we completely dam up the Mississippi so we don
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Not to be all green but... (Score:2)
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Salmon aren't needed. Only water. ;)
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how new is this? (Score:2)
Just like a potato battery... (Score:2)
It looks like a potato battery (that we used to make little clock kits back in the 80s) or any galvanic battery dating back 100+ years, but with a tweak to get more out of it, implemented on a larger scale, and slapped with a "New and Improved, now with NANOTECHNOLOGY" sticker.
On a commercial scale? (Score:2)
I think what's new isn't the basic science, but the R&D to try to scale this up to commercial size power plants?
Still, I can't help but think that at some point, this is going to create contention somewhere between some peoples' need for fresh water, and other peoples' need for electricity.
I guess the idea is that places like the Mississippi Delta where a lot of fresh water is just dumping into the ocean (and being "wasted") *anyhow*, it wouldn't hurt to put such a power plant.
Can we get a comparison to hydroelectric? (Score:2)
The Stanford team has calculated that with 50 cubic meters (more than 13,000 gallons) of fresh water per second, a power plant based on this technology could produce up to 100 megawatts of power.
I can't find any facts detailing the flow of water through various hydroelectric dam turbines to compare to this, but 100MW from 50m^3/s seems very efficient.
Also deep wells (Score:3)
In Florida most drinking water is obtained from wells. Deep wells tend to be brackish and require desalination of the water to be usable. It would seem then that a combination use of waste water and deep well water would work. Also the battery sounds like it acts as a desalination device during discharge so it might serve the purpose of both desalination and power generation.
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In Florida most drinking water is obtained from wells. Deep wells tend to be brackish and require desalination of the water to be usable.
So that explains why Florida has some of the worst-tasting drinking water in the entire country.
The Silver Electrode is very expensive? (Score:2)
From the article:
"The Stanford scientists are currently working on modifications to get the battery ready for commercial production. For example, the silver electrode is very expensive, and they hope to develop a cheaper alternative."
I'm really at a loss on this. How expensive can a silver electrode be, if you're producing enough power to charge for it? Silver while pricey (currently ~ $39.00/oz) It's just a tad more expensive than Lithium (currently ~ $31.50/oz) and if this thing really worked. they'd pay
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Wouldn't this "leach" material from the electrodes (Score:2)
Normally, batteries work by leaching material from one electrode into the water, while precipitating ions on the other. By draining the battery, you actually "consume" one of the electrodes. Recharging work if the process can be reversed.
However, if the electrolyte is changed between charging and decharging, effectively the manganese dioxide or silver ions dissolved are now gone, which has two effects:
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Isn't the chlorine the material that is exchanged? Not the actual electrodes?
Indeed, you are right. Both electrodes absorb salt ions [rsc.org]: chlorine is taken up by the silver electrode and sodium is taken up by the manganese dioxide electrode.
Hmmm, impressive how the manganese dioxide can stabilize the sodium, hehe...
Congrats, props from me (Score:3)
In learning about thermodynamics I had learned that, where there's a gradient, you can extract energy, be it a gradient of temperature, electrical field ... or even chemical concentration. But it's one thing to know it's theoretically possible, and another thing to actually pull it off in a way that extracts meaningful energy. Good work, scientists and engineers.
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Well done.
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Glad to hear it! But I didn't know I was saying something all that insightful or demonstrative of thermodynamics understanding.
It is kind of counterintuitive that you'd be able to extract energy just because there's a difference in concentration between two bodies, but it makes more sense once you've read about the Gibbs paradox (esp. Jaynes's handling) and how you can power a mechanical device by using membranes that differ in their permeability to the different constituents of the mixture.
But man, if eve
Consumables? (Score:2)
As always, it's a scale problem. (Score:5, Informative)
The average combined cycle plant is (at a minimum) around 400MW. Not including co-gens, etc. Just normal power plants sitting out in the middle of nowhere. Fukishima is around 4900MW. Fukishima isn't really fair because it is, by any measure, a large nuke plant. But, 400-1200MW is not an unreasonable range for "typical" power plants in the US, regardless of the technology used (coal, nuke, combined cycle, direct fire, etc)
At 400MW, you are talking 52,000 gallons PER SECOND of water flow. That, by any measure, is a shitload of flow. At 1200MW, we are talking 156,000 gallons per second.
For comparison, I just looked up the flow rate of the Mississippi river at the high water dam near Lake Itasca. Going thru the Upper St Anthony's falls lock and dam, the flow rate is around 90,000 gal/sec [nps.gov].
So for ONE reasonably sized power plant, you would need fresh water flow that is the equivalent of the Mississippi River.
As I said, it's a scale problem.
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In comparison, the hoover dam generates 2.08 GW, and niagara falls 2.4 GW. And in the most extreme case, the three gorges dam does 18.2 GW.
It may work on small scales, but it cannot compete with hydroelectric on a large scale.
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Uh, you are looking through the telescope the wrong way. That flow you quoted is at the UPPER end. From the same site you linked to, the flow is 50 times greater at the Delta, where you find the OTHER side of the cell, salt water.
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If you diverted a quarter of the flow (probably possible, if not practical), you could supply a plant that provides over 8000MW. It would certainly be a big facility, but that's also a lot of electricity.
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Mmmm! Catfish sushi!
(And, considering the water quality, it comes with e coli sauce.)
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Wow, two fallacies in one!
A sweeping generalization AND a stunning ignorance of the hydrologic cycle.
Well done good sir, well done *slow clap*
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From TFA:
So potable water isn't necessarily needed.
I'm surpised nobody has noted this alternative (Score:2)
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who needs fresh water when you can use pee ?!!!
This comment sponsored by Bear Gryllis
Re:ALready an energy shortage there. (Score:4, Informative)
Wait, you actually think water is disappearing, going poof? Where do you think this water is going? Water is not something you use up and then there is no more. You see, it evaporates, and then it rains down again clean. Now it may not be where you expected it would be, or it may end up unfit for use in areas with contaminants, but the water is still there.
You realize there are nearly inexhaustible supplies under the ground right? If you suck it out faster than it seeps back down, guess what, the water still exists. We could potentially use it faster than we harvest it, but to assert that water is a scarce resource is very, very misleading. You can always expand your collection techniques.
Or are you suggesting we are in danger of locking up *all* of the hydrogen and oxygen on the earth in to other compounds?
Oh, you know that salt water? Let it evaporate, and magically you have more fresh water. :P
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It's a good thing that Standford isn't in the UAE then.
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They could easily have free/nearly so fresh water for everyone, but those areas are generally run by less forward thinking leaders. Recently there has been some move to change that, but seems to have tapered off.
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The same way roads and all other government projects are funded.
Excluding the UAE, most of the middle east could easily fund such projects with a tax on exported oil. Not all UAE nations export enough oil, so they could then have their various sheiks pay for it. Desalination is a well understood technology.
Truthfully though, these nations have other problems perhaps even more pressing. By that I mean the political issues that have created the current situation to begin with.
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i'm not sure personally but i have a feeling that if they focus their interest in providing fresh water rather than other crap
http://www.dailymail.co.uk/sciencetech/article-1094797/Worlds-refrigerated-BEACH-built-luxury-hotel-Dubai.html [dailymail.co.uk]
just an example.... i'm sure if they refocused their efforts they could solve the problem.. but again its all about priorities.
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What they didn't tell you is that the process actually involves Ice-9, so yeah, we're going to use up all the available liquid water and then die.
Cool battery though.
Re:ALready an energy shortage there. (Score:5, Interesting)
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You might want to Google "photosynthesis". Major rivers no longer reach the ocean because we've diverted them for use in industrial agriculture. And yes, that water really does cease to exist as water.
Of course, realistically, most of it ends up going to waste, either soaking into the ground or evaporating; Yes, we can theoretically reduce those losses drastically, but as it stands, for both human consu
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Ground water isn't a closed system in any sense. If water is taken from an aquifer at a rate greater than it is replenished then the level of the aquifer will fall and even temporarily dry up until the water levels can replenish, this could take a months, years or even centuries dependent on local geography and climate.
In many places, aquifer depletion is a major engineering obstacle necessitating boreholes to be drilled ever deeper to maintain their rate of water extraction until the point they are simply
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I said you can extract if faster than it is replinished, but it really is inexhaustable. You will not run out. Once the reserve is gone, you can only get it as fast as it seeps down, but it isn't *gone*
The point of the post was that people are far too accepting of the concept that *everything* is scarce. Water just isn't one of those things.
The planet will not run out of water. It just isn't going to happen. Sure, we might have to move usage around a bit in some cases, but the idea that water will magi
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My first thought was they build a desalination plant right next door that operates off hydro or solar power.....
Solar may be plausible...but I think there's a major flaw in the idea of a hydro-powered desalinization plant: places that have enough flowing river water for hydro don't need desalinization plants.
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If you've ever had tap water from a town along the Mississippi River, you're probably drinking some thousands of other humans' piss. Possibly even you own, if you drive south along the river. Towns on big rivers don't drill for water. They treat the river water for drinking, then treat the sewage and release it back into the river.
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Something tells me that the entire estuary will have to be blocked to generate 1/16th of the coal plant's output.
Re:Great News for Environment! (Score:4, Informative)
From TFA:
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Re:Great News for Environment! (Score:4, Funny)
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Actually I heard the dealers call it "cha-ching" or something like that.
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Parent is more likely just plain old contrarian, than "environmentalist."
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Environmentalists have a bad name because the industries that are doing all the damage find character assassination easier than actually cleaning up their mess.
Rigggght.... It's all a big conspiracy against environmentalists perpetrated by the big bad corporations. Environmentalists [huffingtonpost.com] have [oregonlive.com] never [pipefinders.com] done [dailymail.co.uk] anything [breitbart.com] to [katu.com] damage [wordpress.com] their [seattlepi.com] own [santacruzsentinel.com] character [stuff.co.nz]
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Not if you do it at the outlet of a river to the sea, where the mixing has been happening for billions of years. I think life in that area has adapted by now.